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Five undescribed norfriedelane triterpenoids, anchietins A-E, along with three known norfriedelane triterpenoids, 21β-hydroxycaloncobalactone, and welwitschiilactones B and C, were isolated from the vine of Anchietia pyrifolia. The compounds were characterized by spectroscopic and crystallographic methods, including 2D NMR spectroscopy and single crystal X-ray crystallography. The isolated compounds were evaluated for the cytotoxic activity against HeLa and HL60 cells and for the inhibitory activity against lipopolysaccharide-induced NO production. Further, inhibitory effects on the inducible nitric oxide synthase mRNA expression levels were also assessed.

Root chemicals and the sequences of the internal transcribed spacers (ITSs) were analyzed for 9 Ligularia kanaitzensis and 3 L. subspicata samples collected in northwestern Yunnan and southwestern Sichuan, China. Subspicatins A and C were isolated from two L. kanaitzensis samples. Introgression of genes responsible for these compounds from L. subspicata was suggested by their strong connection with L. subspicata/L. lamarum and the geographical proximity of the samples to L. subspicata. DNA analysis of a set of 27 L. kanaitzensis samples including those analyzed previously showed that they belong to two clades, designated A and B. Together with the presence/absence of furanoeremophilane, the 27 samples were sorted into three groups: clade A/furan, clade B/furan, and clade B/non-furan. The ancestral plant presumably belonged to clade B/non-furan, because furanoeremophilanes are biosynthesized from eremophilan-8-ones. 1β-Angeloyloxyfukinone, a likely intermediate between fukinone and subspicatin C, was isolated for the first time. This finding allowed us to propose plausible biosynthetic pathways of subspicatins A and C.

Anchietea pyrifolia, commonly known as woody liana, belongs to the Violaceae family and is being used in Brazil as a herbal medicine with anti-inflammatory, anti-allergic, and depurative properties. However, our knowledge on the phytochemicals that confer pharmacological properties to the plant extract remains limited. We report the identification of three new friedelane-type triterpenes (1, 2a, 2b) and a new 30-norfriedelane triterpene (3) together with nine known compounds (4-12) that were isolated from the liana stems of A. pyrifolia. The structures of these compounds were elucidated by spectroscopic methods, including HRMS, and 1D/2D-NMR. In vitro cytotoxicity was assessed against two human cancer cell lines, HeLa and HL-60. The new triterpenes 1-3 and known compounds 9, 11, and 12 exhibited moderate activity with IC50 values ranging from 5.7 to 45.0 μM.

Two new Erythrina alkaloid glycosides, 1 and 2, and three new diarylpropanoid glycosides 12–14 together with nine known compounds were isolated from the MeOH extracts of the seeds of Erythrina velutina. The structures and absolute configurations of these new compounds were elucidated through comprehensive spectroscopic analyses as well as experimental and calculated ECD data. The inhibitory potency of these compounds against nitric oxide production in LPS-induced RAW 264.7 cells and the cytotoxicity of these compounds against the HeLa and HL-60 human cancer cell lines were also discussed.

Canthin-5,6-dione is a common structure of the fluorescent natural products amarastelline A and nigakinone. Here, we synthesized various derivatives, and studied their fluorescence properties. The effects of substituent groups at the N 3 -, 4- and 10-positions were clarified. N 3 -Substitution influenced the solvent-dependent fluorescent change by modulating tautomerization between canthin-5,6-dione and the 5-hydroxy-6-one form. 10-Substitution also influenced the fluorescence, especially in aqueous solution, in combination with N 3 -substitution. Among the synthesized compounds, 5 showed an ‘OFF-ON-OFF’-type fluorescence change with increase of pH, and therefore served as a novel fluorescent sensor for a specific range of pH. Our findings suggest that canthin-5,6-dione should be useful as a fluorophore moiety for fluorescent labeling of biomolecules and for development of fluorescent probes and sensors.

A new pimarane-type diterpenoid, sucupiol (1), and nine known furanocassane-type diterpenoids, vouacapane (2), 7β-hydroxyvouacapane (3), 7β-acetoxyvouacapane (4), 6α-hydroxyvouacapane (5), 6α-acetoxyvouacapane (6), sucutinirane F (7), sucutinirane E (8), 6α, 7β-diacetoxyvouacapane (9), and 6α, 7β-diacetoxyvouacapane-14β-al (10), were isolated from the seeds of Bowdichia virgilioides and their structures were elucidated by using 2D NMR data. The isolation of 1 provides evidence to support the presence of intermediate A in the course of biosynthesis of furanocassane-type diterpenoids.

A highly efficient and simple method for the synthesis of 2-alkylbenzothiazoles through the condensation of 2-aminothiophenol and aliphatic aldehydes in the presence of active carbon/silica gel is described. The reaction proceeded under solvent-free and microwave irradiation to afford 2-alkylbenzothiazoles in high yields. This method was extended to the synthesis of bile acid derivatives containing a benzothiazole ring and obtained the desired products in high yields. The anti-inflammatory activity and cytotoxicity of the newly synthesized benzothiazole derivatives of bile acid were tested; the results showed that anti-inflammatory activities of all tested compounds tested were higher than that of standard drugs, such as indomethacin.

Four new eremophilane type sesquiterpenoids, a new bakkane type sesquiterpenoid, and a new secoeremophilane type sesquiterpenoid were isolated from Ligularia brassicoides Hand.-Mass. (Asteraceae) collected in China, and were an epoxy lactone derived from 6-acyloxyeuryopsin 1, 6-acyloxy-9oxoeuryopsin 2, 6-acyloxy-9-oxofuranoeremophilane 3, 6-acyloxyeuryopsin 4, 6-acyloxy bakkane type epoxy lactone 5, and secovirgaurenol 6-O-(2'-hydroxymethyl)acrylate (6), respectively. All but one had a 2'-hydroxymethylacryloyloxy group at C-6. This is the first study to describe the chemical constituents of this species. (C) 2014 Elsevier Ltd. All rights reserved.

Twelve new furanocassane diterpenoids, sucupiranins A–L (1–12), and three known compounds (13–15) were isolated from the seeds of Bowdichia virgilioides. The structures of the compounds were elucidated via 1H and 13C NMR analysis, including 2D NMR (1H–1H COSY, HSQC, HMBC, and NOESY); HRMS data; and X-ray crystallographic analysis. The absolute configurations were defined using their electronic circular dichroism (ECD) spectra by applying the exciton chirality method to the bis-p-bromobenzoate of compound 13. Sucupiranin J (10) inhibited lipopolysaccharide-induced nitric oxide production (IC50 30.6 μM), whereas sucupiranins J (10), K (11), and 13 exhibited weak antimalarial activity against Plasmodium falciparum K1 with IC50 values of 32.2, 23.5, and 22.9 μM and selectivity indices of 4.3, 1.9, and >12.0 (MRC-5/K1), respectively.

Five new 12-oxygenated eremophilane sesquiterpenoids bearing a B-ring enone system were isolated from Ligularia lingiana S.W. Liu (Asteraceae) collected in China. Compound 5 was a Diels-Alder adduct of 3 alpha-angeloyloxy-7 beta H-8-oxoeremophila-9,11(13)-dien-12-al and the monoterpene, ocimene. Compound I showed cytotoxic activities against HeLa, HL60, Jurkat, and NIH-3T3 cells at IC50 0.0407, 0.440, 0.313, and 3.48 mu M, respectively. (C) 2014 Elsevier Ltd. All rights reserved.

Two novel N-acyl amidated bile acids, N-methyltaurine conjugated cholic acid and N-methyltaurine conjugated deoxycholic acid, were found to be major biliary bile acids in two species of angelfish the regal (Pygoplites diacanthus) and the blue-girdled (Pomacanthus navarchus) angelfish. The identification was based on their having MS and NMR spectra identical to those of synthetic standards. A survey of biliary bile acids of 10 additional species of angelfish found 7 with N-methyltaurine conjugation. In all 12 species, conjugated deoxycholic acid (known to be formed by bacterial 7-dehydroxylation of cholic acid) was a major bile acid. In all previous studies of biliary bile acids in fish, deoxycholic acid has been present in only trace proportions. In addition, bile acid conjugation with N-methyltaurine has not been detected previously in any known vertebrate. N-methyltaurine conjugated bile acids are resistant to bacterial deconjugation and dehydroxylation, and such resistance to bacterial enzymes should aid in the maintenance of high concentrations of bile acids during lipid digestion. Our findings suggest that these species of angelfish have a novel microbiome in their intestine containing anaerobic bacteria, and describe the presence of N-methyltaurine conjugated bile acids that are resistant to bacterial attack.

Kiusianins A-D (1-4) were isolated from the leaves of a Japanese endemic plant, Tilia kiusiana, together with 14 known compounds. The structures of a new lanostane-type triterpenoid 1 and three new cholestane-type sterols 2-4 were elucidated by spectroscopic methods, including two dimensional (2D) NMR. All the compounds isolated were evaluated for their cytotoxicity against two human cancer cell lines, HeLa and HL-60.

Five new furanocassane-type diterpenoids, sucupiranins M–Q (1–5) were isolated from the seeds of Bowdichia virgilioides. Their structures and stereo chemistries were elucidated on the basis of spectroscopic analyses including HRESIMS, 2D NMR (1H-1H COSY, HSQC, HMBC, and NOESY), and ECD spectra.

Four new compounds, rearranged noreremophilan-8,6-olide, rearranged dinoreremophilanone, epoxy gamma-lactone, and 2 alpha-hydroxyermophil-11-en-9-one, along with eremophilenolides related to ligularol and other known terpenoids, were isolated from Ligularia virgaurea (ligularol type) collected from the northern Sichuan Province of China. Three of the new compounds had degraded and unique structures. The absolute configuration of 2 alpha-hydroxyermophil-11-en-9-one was determined on the basis of density functional theory calculation. The back octant rule cannot be applied to this compound because of the contribution of the hydroxy group to the front octant. (C) 2013 Elsevier Ltd. All rights reserved.

Erythraline, isolated from the bark of Erythrina crista-galli which are used as Brazilian medicine plant for the treatment of inflammation diseases, suppressed nitric oxide (NO) production and induction of inducible nitric oxide synthase (iNOS) expression in RAW264.7 cells stimulated by lipopolysaccharide (LPS). Because of Toll-like receptor (TLR) 4 and its signal transduction are indispensable to the production of NO and iNOS expression by LPS, we investigated the effects of erythraline on TLR signaling molecules. Western blot analysis revealed that the degradation of inhibitor of nuclear factor (NF)-κB (IκB) by LPS was suppressed by erythraline. Moreover, erythraline inhibited not only LPS-induced phosphorylation of IκB kinase (Ikk) but also phosphorylation of mitogen-activated protein kinases (MAPKs). However, it showed no effect on LPS -induced phosphorylation of transforming growth factor (TGF)-β-activated kinase (TAK) 1 that exists upstream of Ikk and MAPKs, and is required for the activation of these signaling molecules on TLR signaling pathway. These results suggested that erythraline might have inhibited the kinase activity of TAK1. Furthermore, these results were supported from the inhibitory pattern of erythraline on TLR signaling molecules when the cells were stimulated by TLR2 ligand, peptidoglycan which activates the same pathway as LPS on TLR signal transduction.

One abietane-type and one dinoricetexane-type diterpenoid, salviskin A (1) and salviskin B (2), respectively, together with fourteen known diterpenoids, were isolated from Salvia przewarskii. Structural elucidation of these compounds was performed by spectroscopic methods including 2D NMR. The compounds isolated were evaluated for their cytotoxicity against HeLa and HL-60 cells.

Two new Erythrinan alkaloids, cristanines A and B (1, 2), were isolated from the bark of Erythrina crista-galli L. together with nine known Erythrinan alkaloids (3-5, 7-12) and an indole alkaloid (13). The structures of the compounds, cristanines A (1) and B (2), were elucidated by spectroscopic methods. Three of the twelve compounds isolated showed significant inhibitory activity on lipopolysaccharide induced nitric oxide (NO) production.

We studied the bioactivities of constituents from two tropical medicinal plants, Cunila spicata and Hyptis fasciculata. These plants found in Brazil belong to the Labiatae family. Four known compounds obtained from these herbs were identified as 3alpha, 24-dihydoxylurs-12-en-28-oic acid, betulinic acid, aurantiamide acetate, and aurantiamide benzoate by spectroscopic means. 3alpha, 24-Dihydoxylurs-12-en-28-oic acid has potent inhibitory activity against Streptococcus salivarius, Streptococcus pneumoniae, Streptococcus pyogenes, and Porphyromomas gingivalis. Aurantiamide benzoate exhibited moderate inhibitory activity against xanthine oxidase. It was clarified that herbs Cunila spicata and Hyptis fasciculata are effective against bronchitis and gout.

Four new eremophilane type sesquiterpenoids [e.g. (I)], a new bakkane type sesquiterpenoid (II), and a new secoeremophilane type sesquiterpenoid (III) are isolated from Ligularia brassicoides collected in China.

isolation, structure elucidation and cytotoxicity of a new lanostane triterpenoid, kiusianin A (I), three new cholestane sterols, kiusianins B (II), C (IIIa), and D (IIIb), and 14 known compounds

Four new oxindole alkaloids, paratunamides A-D (1-4), containing a secologanin unit, were isolated from the bark of Cinnamodendron axillare, and their structures and relative configurations were elucidated by spectroscopic data. The absolute configuration at C-7 in 1-4 was assigned as S, S, R, and S, respectively, on the basis of the CD spectra.

Three novel quaternary indole alkaloids with an unprecedented 1-azoniatricyclo[4.3.3.0(1,5)]undecane moiety, subincanadines A-C (1-3), as well as two new indole alkaloids with a 1-azabicyclo[5.2.2]undecane moiety, subincanadines D (4) and E (5), and a new indole alkaloid with a 1-azabicyclo[4.3.1]decane moiety, subincanadine F (6), have been isolated from the barks of Aspidosperma subincanum Mart, and the structures of 1-6 and the stereochemistry of 1-3 were elucidated by spectroscopic data and chemical means.

Two new flavonolignans, mururins A and B ( 1 and 2), and a new lignan, mururin C ( 3), were isolated from the bark of Brosimum acutifolium Huber together with three known lignans. Their structures were elucidated by spectroscopic means and chemical modifications. They were tested for protein kinase A (PKA) and protein kinase C (PKC) inhibitory activity. Mururin A showed 3 % and 63 % inhibition to PKA and PKC, respectively, at 20 microM. Mururin B showed 58 % and 38 % inhibition, respectively. Mururin C did not have significant activity.

Four known compounds have been isolated from the aerial parts of the Brazilian medicinal plant Pariparoba (Pothomorphe umbellata). They were an alkaloid, a flavone, a dihydrocalcone, and a steroid. The chemical structures were established to be N-benzoylmescaline, wogonin, uvangoletin, and beta-sitosterol glucoside using spectral methods. Among these compounds, the main component N-benzoylmescaline showed significant antibacterial activity against Helicobacter pylori.

A termolecular condensation reaction of harmane, alkyl halide, and dimethyl oxalate has been developed for the construction of a variety of canthin-5,6-diones. The carbon skeleton of amarastelline A, a fluorescent canthin alkaloid, was synthesized in 99.8% yield by applying this procedure.

From the roots of Ligularia cymbulifera collected in Yunnan Province, China, two new eremophilane-type sesquiterpenoids (1 and 2) together with ten known compounds (3–12) were obtained through the precise chemical component elucidation. The structure determination was mainly carried out with 1D and 2D NMR data.

A new diterpenoid with a rearranged skeleton, prattinin A (1), was isolated along with five known compounds (2–6) from the roots of Salvia prattii. The structure of 1 bearing a methyl group at the C-5 position was established by extensive spectroscopic analyses and the absolute configuration of 1 was elucidated by comparing the calculated and experimental electronic circular dichroism (ECD) spectra. Compounds 1, 3, 4, and 5 exhibited moderate or weak cytotoxicity against HL-60 and HeLa cell lines.

A novel compound, named salviskinone A (1), was isolated from Salvia przewarskii. The compound has a rearranged carbon skeleton with a methyl unit at C-5 from abietane-type diterpene. Its structure and relative stereochemistry were elucidated by detailed spectroscopic analysis, including HREIMS and 2DNMR (COSY, HSQC, HMBC, and NOESY) spectra. (C) 2011 Elsevier Ltd. All rights reserved.

Kiusianins A-D (1-4) were isolated from the leaves of a Japanese endemic plant, Tilia kiusiana, together with 14 known compounds. The structures of a new lanostane-type triterpenoid 1 and three new cholestane-type sterols 2-4 were elucidated by spectroscopic methods, including two dimensional (2D) NMR. All the compounds isolated were evaluated for their cytotoxicity against two human cancer cell lines, HeLa and HL-60.

We report an improved synthesis of the (22R)- and (22S)-epimers of 3α,7α,12α,22-tetrahydroxy-5β-cholan-24-oic acid and 3α,7α,22-trihydroxy-5β-cholan-24-oic acid from cholic acid (CA) and chenodeoxycholic acid (CDCA), respectively. The principal reactions involved were as follows: (1) oxidative decarboxylation of the bile acid peracetates with lead tetraacetate, and (2) subsequent Reformatsky reaction of the 23,24-dinor-22-aldehydes with ethyl bromoacetate in the presence of activated Zn as a catalyst with the reaction temperature maintained precisely at 75 °C. The absolute configuration of the chiral center at C-22 of each epimer was established by single-crystal X-ray diffraction data using its ethyl ester-peracetate derivative. The (1)H- and (13)C-NMR spectra that permit the (22R)- and (22S)-epimers to be distinguished are reported as well as the specific (1)H shift effects induced by C(5)D(5)N. Bile acids having hydroxyl groups at C-22 are present in a variety of animal biles, previously have been difficult to identify, and are known to have distinctive physicochemical and biological properties.

Three new labdane diterpenoids, pacovatinins A-C (1-3), were isolated from seeds of the Brazilian medicinal plant Renealmia exaltata ("Pacová-catinga"), and their structures including absolute configurations were elucidated by spectroscopic data and a modified Mosher method.

Four new nitrogen-containing clerodane diterpenoids, echinophyllins C-F (1-4), were isolated from the leaves of the Brazilian medicinal plant Echinodorus macrophyllus ("Chapéu-de-couro"), and their structures and relative stereochemistry were elucidated from their spectroscopic data. Compounds 1-4 possess an alpha,beta-unsaturated gamma-lactam ring consisting of a clerodane diterpene unit and an amine moiety.

Two novel nitrogen-containing clerodane diterpenoids, echinophyllins A (1) and B (2), were isolated from the leaves of the Brazilian medicinal plant Echinodorus macrophyllus (‘Chapeu-de-couro’), and their structures and relative stereochemistry were elucidated by spectroscopic data. Echinophyllins A (1) and B (2) possess a unique α,β-unsaturated γ-lactam ring consisting of a clerodane diterpene and a tyramine unit or N-feruloyl putrescine unit, respectively.

One new ent-neosecurinane-type alkaloid, secu’amamine E (1), and two novel alkaloids consisting of a ent-neosecurinane and a piperidine unit, secu’amamine F (2), and secu’amamine G (3), were isolated from Securinega suffruticosa var. amamiensis. Their structures and stereochemistry were elucidated on the basis of spectroscopic analyses.

A selective potent anti-Helicobacter pylori isoflavone was isolated from a Brazilian Medicinal Plant, Myroxylon peruiferum. The isolation bioassay-guided and the characterization of an active anti-H. pylori constituent was performed using the methanol extract of plant of minute amount. The active compound was identified as cabreuvin (1), an isoflavone derivative. The structure-activity relationships of several related compounds were also investigated.

An instance is presented in which skeletal features of chemical constituents provide valuable information on the phylogenetic relationship in plant species. A close examination of diterpenoid constituents was carried out on three Portulaca species, each of which has a different basic chromosome number. Major diterpenoid constituents in P . cv. Jewel, P. pilosa and P. grandiflora were found to be, respectively, of the clerodane ([6.6]-fused ring), prinziane ([7.6]-fused ring) and portulane ([7.5]-fused ring) types. From a biosynthetic viewpoint, a linear evolutionary relationship among the Portulaca plants in question would be assumed. All the diterpenoids found in the above three species have 1,4-dihydroxy-2-buten-2-ylethyl side chains and the relevance of this feature for chemical systematics of Portulaca plants is pointed out.

Two known flavonoids were isolated from a tropical medicinal plant, Hyptis fasciculata (Labiatae), found in Brazil. Flavonoids were identified as cirsilineol (1) and cirsimaritin (2) by spectroscopic means and were exhibited potent antibacterial activity against Helicobacter pylori, and cirsilineol (1) had weak antibacterial activity against Escherichia coli and Salmonella enteritidis. Following up on the relationship between anti-H. pylori activity and flavonoids with methoxy groups, several methoxy flavonoids were evaluated for proliferation of H. pylori.

A novel indolizidine alkaloid, secu'amamine A (1), was isolated from the leaves and twigs of the medicinal plant, Securinega suffruticosa var. amamiensis together with securinine (2). The structure and relative stereochemistry of 1 was elucidated by spectroscopic data and its absolute configuration was assigned on the basis of the OMe-madelate method.

Fifteen Isodon diterpenoids (1-15) were evaluated for their cytotoxic activity against HeLa and HL-60 human cancer cell lines, and against murine vincristine (VCR)-resistant P388 cells. Kamebanin (14) showed efficient cytotoxic activity against HeLa and HL-60 cells. In addition, although dihydroenmein (2) and trichorabdal B (7) were inactive against several tested cell types, they were found to have cytotoxic-enhancing activity of VCR against VCR-resistant P388 cells.

Two new norursane-type triterpenoids were isolated from Dipsacus chinensis (Dipsacaceae) collected in China. The structures were determined based on the spectroscopic data to have enol forms of ene-dione and dione structures in ring A, respectively.

The chemical constituents of the root extracts and the evolutionarily neutral DNA base sequences were studied for 28 samples of Ligularia duciformis, L. kongkalingensis, and L. nelumbifolia collected in Sichuan and Yunnan Provinces of China. The samples could be classified into four chemotypes (1-4). Sesquiterpenoids having eremophilane and oplopane skeletons were isolated from two (Chemotype 1) and three (Chemotype 2) samples, respectively. Two new oplopane derivatives were isolated and their structures were determined. In 18 samples, phenylpropenoids were the major components (Chemotype 3). In five samples, neither phenylpropenoids nor sesquiterpenoids were found (Chemotype 4). Despite this large chemical variety, no correlation was found between the chemotype and the morphological criteria of species identification. The analysis of the evolutionarily neutral DNA regions also indicated that the samples were not separated into distinct clades and that introgression was extensive.

An extremely potent antitumor neo -clerodane diterpene was isolated from the oleoresin of the Brazilian medicinal plant, Copaifera langsdorfii Desfon. This compound was identified as (-)-kolavenol 1 . The antitumor effect of 1 against IMC carcinomas as determined from the increase in lifespan (I.L.S.) in mice was twice that of 5-FU. The structure elucidation and the antitumor activity of the other related compounds 2 ∼ 6 in this oleoresin were also described.